52. Exemplar exercise problem XII

1. Justify whether it is true to say that \(–1,\frac{3}{–2},–2,\frac{5}{2},...\) forms an AP as \(a_2– a_1= a_3– a_2\).

The given statement is FalseTure.

 

2. For the AP: \(–3, –7, –11, ...\), can we find directly \(a_{30} – a_{20}\) without actually finding \(a_{30}\) and \(a_{20}\)? Give reasons for your answer.